Conventionally, an idling reduction system has been proposed that generates electric power when a vehicle is in motion by driving an alternator using rotational torque from an engine that is transmitted by means of a belt, and that restarts the engine when the vehicle is stopped by supplying electric drive power to operate the alternator as a motor (see Patent Literature 1, for example).
An electrically-powered motor turbocharging systems have also been proposed in which a super-high-speed rotary machine (a motor) and a turbine that is driven by exhaust gas are disposed so as to be coaxial with a compressor that compresses intake gas to solve a lag in boost pressure in a low-speed rotation range of a turbocharger when an attempt is made to obtain high output by compressing engine intake air using the turbocharger (see Patent Literature 2, for example).
Patent Literature 1: Japanese Patent Laid-Open No. 2005-328690 (Gazette)
Patent Literature 2: Japanese Patent Publication No. 2005-500452 (Gazette)